α-Glucosidase inhibitors are known to delay carbohydrate absorption and control postprandial blood glucose. Olive fruits are rich in polyphenols, yet systematic studies on the influence of fruit maturity on the biological activities of these polyphenol extracts remain scarce. This study aimed to compare the α-glucosidase inhibitory mechanisms and in vitro antioxidant capacities of free polyphenol extracts from olive fruits at different maturity stages, as well as their major individual phenolic constituents. Free polyphenols were extracted using organic solvents, and their IC50 values against α-glucosidase were determined. Furthermore, inhibition types and binding sites were investigated through enzyme kinetics and molecular docking, while antioxidant activities were evaluated via DPPH, ORAC, and Fe2+ chelating assays. The results showed that GFP （IC50 = 0.39 mg·mL-1）exhibited significantly higher inhibitory activity than MFP （IC50 = 0.59 mg·mL-1）. Among the tested phenolic monomers, luteolin exhibited the strongest inhibitory activity, with an IC50 value of 26.70 μg·mL-1. Enzyme kinetic analysis revealed that GFP, MFP, rutin, and chlorogenic acid acted as mixed-type inhibitors, whereas luteolin exhibited noncompetitive inhibition. Molecular docking indicated that luteolin primarily bound to nonactivesite residues such as GLN350 and ASP349. In addition, all samples exhibited potent in vitro antioxidant activities; luteolin showed the best overall activity, while GFP demonstrated the strongest Fe2+ chelating capacity. Overall, olive polyphenols possess promising functionality as both αglucosidase inhibitors and antioxidants, supporting their potential application in natural hypoglycemic agents and functional foods.